Specific killing of latently HIV-1-infected cells after provirus reactivation

项目摘要/摘要 HIV-1大流行已经夺走了2000多万人的生命，目前全球有3860万人感染， 并将继续成为一个重大的全球健康问题，因为没有疫苗可用。目前，唯一的 对HIV-1感染有效的治疗方法是HAART(高效抗逆转录病毒疗法)，它导致了 与艾滋病毒-1相关的发病率和死亡率大幅下降。然而，HAART未能在 活体，主要是由于具有复制能力的长期潜伏感染细胞的持续存在 前病毒。清除这些受感染细胞的努力主要集中在重新激活前病毒。据推测， 这些被感染的细胞会在病毒的细胞病变作用下重新激活病毒基因表达后被杀死 (CPE)、宿主免疫反应或两者兼而有之。几种兴奋剂，包括IL-7，丙戊酸(VPA)，琥珀酰苯胺 异羟肟酸(SAHA)和前列环素已被探索在潜伏感染患者中强制激活前病毒 静息的CD4T细胞，构成体内HIV-1的主要储存库。然而，使用IL-7或VPA治疗 服用HAART的患者未能减少HIV-1潜伏期，这表明仅有这些药物不足以 诱导杀死潜伏感染的细胞。我们建议开发一种“激活-杀死”方法，通过结合 前病毒刺激剂，其试剂能够在患者体内自然安装抗HIV-1免疫 HIV-1感染在前病毒重新激活后特异性地杀死潜伏感染的细胞。研究表明，两者都 HIV-1感染细胞和病毒粒子使用其表面补体激活调节剂(RCA)来抵抗抗体-1 依赖补体介导的溶解(ADCML)，这解释了为什么强有力和持续的抗HIV-1 几乎所有感染者的包膜(Env)抗体(Ab)反应都无法控制HIV-1感染。我们和 其他人报告说，阻断人类CD59(HCD59)，RCA的关键成员，使两个HIV-1感染 对ADCML敏感的细胞和病毒粒子。因此，我们假设向SAHA添加hCD59抑制剂， 前列腺素或两者兼而有之将使HIV-1感染者体内天然存在的抗HIV-1环境抗体能够触发 潜伏感染T细胞在前病毒激活后的ADCML。前病毒刺激剂将激活前病毒以 在潜伏感染的细胞表面表达病毒蛋白，如果hCD59被抑制，ADCML将杀死这些病毒蛋白。 我们将使用人类T细胞系ACH2，一个很好地描述HIV-1潜伏期的模型，来开发这样一种 进场(目标1，R21阶段)。我们将验证该方法是否能够触发主服务器的ADCML 体外潜伏感染HIV-1的CD4T细胞(AIM 2，R33期)。然后我们将确定这种方法是否 可以允许感染患者血清中自然存在的抗HIV-1抗体触发其自身的ADCML 自身潜伏感染的静息CD4T细胞(AIM 3，R33期)。我们的项目具有创新性和重大意义 因为我们的目标是开发一种新的方法来清除患者体内持续存在的HIV-1病毒 哈尔特。该方法可以同时针对各种潜伏感染细胞和残留病毒血症， 有可能导致对各种持久的艾滋病毒-1宿主的更广泛的影响和更好的疗效。

PROJECT SUMMARY/ABSTRACT The HIV-1 pandemic has claimed over 20 million lives, with 38.6 million people worldwide currently infected, and will continue to be a significant global health problem as there is no vaccine available. Currently, the only effective treatment available to HIV-1 infection is HAART (highly active antiretroviral therapy), which has led to a profound reduction in HIV-1-related morbidity and mortality. However, HAART fails to eliminate the virus in vivo, mainly due to the persistent existence of long-lived latently-infected cells harboring replication-competent proviruses. Efforts to purge these infected cells have focused on reactivation of the proviruses. It is presumed that these infected cells will be killed after reactivation of virus gene expression by viral cytopathic effects (CPEs), host immune responses or both. Several stimulants including IL-7, valproic acid (VPA), suberoylanilide hydroxamic acid (SAHA) and prostratin have been explored to force activation of proviruses in latently-infected resting CD4+ T cells that constitute the major reservoir of HIV-1 in vivo. However, treatment with IL-7 or VPA in patients on HAART has failed to reduce HIV-1 latency, suggesting that these agents alone are not sufficient to induce killing of latently-infected cells. We propose to develop an “activation-killing” approach by combining provirus stimulants with an agent that is able to allow anti-HIV-1 immunity naturally mounted in patients during HIV-1 infection to specifically kill latently-infected cells after provirus reactivation. Studies have shown that both HIV-1-infected cells and virions use their surface regulators of complement activation (RCA) to resist antibody- dependent complement-mediated lysis (ADCML), which explains why vigorous and sustained anti-HIV-1 envelope (Env) antibody (Ab) responses in almost all infected individuals fail to control HIV-1 infection. We and others have reported that blocking human CD59 (hCD59), a key member of RCA, renders both HIV-1-infected cells and virions sensitive to ADCML. We therefore hypothesize that addition of an hCD59 inhibitor to SAHA, prostratin or both will enable anti-HIV-1 Env Abs naturally present in HIV-1-infected individuals to trigger ADCML of latently-infected T cells after provirus reactivation. The provirus stimulants will activate proviruses to express viral proteins on the surface of latently-infected cells that will be killed by ADCML if hCD59 is inhibited. We will use the human T cell line ACH2, a well-characterized model of HIV-1-latency, to develop such an approach (Aim 1, R21 Phase). We will verify whether the approach is able to trigger ADCML of the primary CD4+ T cells latently infected with HIV-1 in vitro (Aim 2, R33 Phase). We will then determine if this approach can allow anti-HIV-1 Abs naturally present in the sera of infected patients to trigger autologous ADCML of their own latently-infected resting CD4+ T cells (Aim 3, R33 Phase). Our project is innovative and significant because we aim to develop a novel approach for purging the persistent reservoir of HIV-1 in patients on HAART. This approach may simultaneously target various latently infected cells and residual viremia, potentially leading to a broader impact and improved efficacy against the various persistent HIV-1 reservoirs.